Substrate treatment method, coating film removing apparatus, and substrate treatment system

ABSTRACT

According to the present invention, during the photolithography processing of a substrate, exposure processing is performed immediately after removal of a coating film on the rear surface of the substrate, and a coating film is formed on the rear surface of the substrate immediately after the exposure processing. Thereafter, etching treatment and so on are performed, and a series of these treatment and processing steps are performed a predetermined number of times. The coating film has been formed on the rear surface of the substrate at the time for the etching treatment, so that even if the coating film gets minute scratches, the rear surface of the substrate itself is protected by the coating film and thus never scratched. Further, since the coating film on the rear surface of the substrate is removed immediately before the exposure processing, the rear surface of the substrate can be flat for the exposure processing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of treating a substrate, forexample, a semiconductor wafer or the like, a coating film removingapparatus, and a substrate treatment system.

2. Description of the Related Art

In photolithography processing in a process of manufacturing asemiconductor device, for example, resist coating treatment of applyinga resist solution above a semiconductor wafer (hereinafter, referred toas a “wafer”) to form a resist film, exposure processing of exposing theresist film to light under a predetermined pattern, and developingtreatment of developing the exposed resist film and so on are performedin sequence, to form a predetermined resist pattern above the wafer.Etching treatment of the wafer is performed using this resist pattern asa mask, and stripping processing of the resist film and cleaning of thewafer are then performed to form a predetermined pattern on the wafer.The process of forming a predetermined pattern in a predetermined layeris generally repeatedly performed 20 to 30 times to manufacture asemiconductor device.

Out of these treatments and processing, the above-described exposureprocessing is performed, for example, by applying ArF laser, KrF laser,or the like to the resist film on the wafer with the rear surface of thewafer being suction-held by a chuck in the apparatus for performing theexposure processing. If, for example, contaminants adhere to the rearsurface of the wafer when the exposure processing is performed, thewafer is not horizontally held by the chuck, thus causing defocus duringthe exposure processing. Accordingly, it is necessary that the wafer ishorizontally held by the chuck, that is, the rear surface of the wafersucked by the chuck is flat, in order to appropriately perform theexposure processing.

Hence, a scribing apparatus including a transfer arm for inverting thefront and rear surfaces of the wafer, a freely rotatable spin chuck forholding the wafer, and a scribing brush for cleaning the front and rearsurfaces of the wafer held by the spin chuck has been conventionallyproposed as an apparatus for removing the contaminants on the rearsurface of the wafer. Conventionally, before performance of the exposureprocessing for the wafer, the scribing apparatus is used to first directthe rear surface of the wafer upward by means of the transfer arm andhold the wafer in this state by means of the spin chuck. The scribingbrush is brought into contact with the rear surface of the wafer whilerotating the spin chuck is rotating, thereby removing the contaminantsadhering to the rear surface of the wafer (Japanese Patent PublicationLaid-open No. Hei 3-52226).

However, even if the contaminants on the rear surface of the wafer areremoved, minute scratches may be generated on the rear surface of thewafer during various kinds of treatments and processing in the processof manufacturing the wafer to cause projections and depressions on therear surface of the wafer. Especially when the etching treatment isperformed, the rear surface of the wafer is likely to get minutescratches if the surface temperatures of the wafer and the electrostaticchuck are increased during the etching treatment due to the differencein coefficient of thermal expansion between the wafer and theelectrostatic chuck holding the wafer. Due to such minute scratches onthe rear surface of the wafer, the wafer is not horizontally held duringthe exposure processing, thus causing defocus.

SUMMARY OF THE INVENTION

The present invention has been developed in consideration of the abovepoints, and its object is to planarize the rear surface of a substratebefore exposure processing in order to appropriately perform theexposure processing with the substrate being horizontally held.

To attain the above object, in the present invention, a substratetreatment method of performing at least photolithography processing andetching treatment for a substrate in this order a plurality of times,includes the steps of forming a coating film on a rear surface of thesubstrate after exposure processing in the photolithography processingis performed; and removing the coating film between the formation of thecoating film and performance of next exposure processing.

According to the substrate treatment method of the present invention,after performance of exposure processing, the coating film is formed onthe rear surface of the substrate, for example, immediately after theexposure processing, so that even if the coating film on the rearsurface of the substrate gets minute scratches, for example, during theetching treatment performed after the photolithography processing andthe transfer of the substrate, the rear surface of the substrate itselfis protected by the coating film and thus never scratched. Since thecoating film on the rear surface of the substrate is then removed beforenext exposure processing is performed, the rear surface of the substratecan be flat without projections and depressions in the exposureprocessing performed after the removal of the coating film. Accordingly,the substrate can be horizontally held during the exposure processing,so that the exposure processing can be appropriately performed. In thiscase, as a matter of course, the step of forming the coating film on therear surface of the substrate may be performed before thephotolithography processing for the first time is performed, and thestep of removing the coating film formed before the photolithographyprocessing for the first time may be performed before exposureprocessing in the photolithography processing for the first time.Thereby, even if the coating film formed on the rear surface of thesubstrate gets minute scratches during performance of treatment stepsprior to the exposure processing performed in the photolithographyprocessing for the first time, for example, the step of forming a resistfilm, and during the transfer of the substrate, the rear surface of thesubstrate itself is protected by the coating film and thus neverscratched. In addition, since the coating film is removed before theexposure processing in photolithography processing for the first time isperformed, for example, immediately before the exposure processing, therear surface of the substrate can be flat for the exposure processing.

The method may further include the step of, immediately before the stepof forming a coating film, cleaning the rear surface of the substrate.This removes the contaminants on the rear surface of the substrateimmediately before a coating film is formed on the rear surface of thesubstrate, thereby ensuring that the coating film is planarized morereliably.

According to another aspect, the present invention is a coating filmremoving apparatus for removing a coating film formed on a rear surfaceof a substrate including a transfer arm transferring the substrate; aturning mechanism supporting the transfer arm and turning the transferarm around a horizontal axis; a raising and lowering mechanismsupporting the turning mechanism and raising and lowering the turningmechanism; a transfer mechanism supporting the raising and loweringmechanism and transferring the raising and lowering mechanism in thehorizontal direction; a substrate holding unit horizontally holding thesubstrate with the rear surface of the substrate directed upward; and aremoving solution supply nozzle supplying a removing solution for thecoating film to the rear surface of the substrate held by the substrateholding unit.

According to the coating film removing apparatus of the presentinvention, the coating film on the rear surface of the substrate can beremoved by directing the rear surface of the substrate upward by meansof the transfer arm and the turning mechanism and supplying the removingsolution from the removing solution supply nozzle to the rear surface ofthe substrate.

A rotating mechanism may be provided below the substrate holding unitfor rotating the substrate holding unit around a vertical axis. Therotating mechanism rotates the substrate held by the substrate holdingunit, thereby allowing the removing solution supplied on the coatingfilm on the rear surface of the substrate to uniformly spread.

The coating film removing apparatus may be located in the same substratetreatment system with the exposure processing apparatus for performingexposure processing on the substrate. A coating film forming apparatusfor forming the coating film on the rear surface of the substrate mayfurther be located in the substrate treatment system. This ensures thatthe removal of the coating film on the rear surface of the substrate,the exposure processing of the substrate, and the formation of thecoating film on the rear surface of the substrate can be performed inline, thus smoothly performing a series of treatment and processing ofthe substrate.

According to the present invention, the rear surface of the substratecan be planarized before exposure processing, thus ensuring thatpreferable exposure processing can be performed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view schematically showing the outline of aconfiguration of a coating and developing treatment system incorporatinga coating film removing apparatus according to an embodiment;

FIG. 2 is a front view of the coating and developing treatment systemaccording to the embodiment;

FIG. 3 is a rear view of the coating and developing treatment systemaccording to the embodiment;

FIG. 4 is a longitudinal sectional view schematically showing theoutline of a configuration of a coating film removing apparatus;

FIG. 5 is a plan view schematically showing the outline of aconfiguration of the coating film removing apparatus;

FIG. 6 is a perspective view of a transfer arm, a turning mechanism anda transfer mechanism;

FIG. 7 is a side view of the transfer arm holding a wafer;

FIG. 8 is a longitudinal sectional view of a spin chuck;

FIG. 9 is a longitudinal sectional view showing a structure of a supportpin of the spin chuck;

FIG. 10 is a longitudinal sectional view schematically showing theoutline of a configuration of a coating film forming apparatus;

FIG. 11 is a plan view schematically showing the outline of aconfiguration of the coating film forming apparatus;

FIG. 12 is a flow showing a procedure of wafer treatment;

FIG. 13 is a longitudinal sectional view schematically showing theoutline of a configuration of a coating film forming apparatus;

FIG. 14 is a plan view schematically showing the outline of aconfiguration of the coating film forming apparatus;

FIG. 15 is a perspective view of a coating nozzle having a dischargeport in a slit form;

FIG. 16 is a longitudinal sectional view schematically showing theoutline of a configuration of a coating film removing apparatus;

FIG. 17 is a plan view schematically showing the outline of aconfiguration of the coating film removing apparatus;

FIG. 18 is a longitudinal sectional view schematically showing theoutline of a configuration of a coating film removing apparatus;

FIG. 19 is a longitudinal sectional view a spin chuck;

FIG. 20 is a longitudinal sectional view schematically showing theoutline of a configuration of a coating film removing apparatus;

FIG. 21 is a plan view schematically showing the outline of aconfiguration of a coating film removing system;

FIG. 22 is a front view of the coating film removing system;

FIG. 23 is a flowchart showing a time to remove the coating film by thecoating film removing system, and a time to form the coating film by thecoating film forming system; and

FIG. 24 is a plan view schematically showing the outline of aconfiguration of a coating film forming system.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, a preferred embodiment of the present invention will bedescribed. FIG. 1 is a plan view showing the outline of a configurationof a coating and developing treatment system 1 as a substrate treatmentsystem incorporating a coating film removing apparatus 200 according tothe embodiment, FIG. 2 is a front view of the coating and developingtreatment system 1, and FIG. 3 is a rear view of the coating anddeveloping treatment system 1.

The coating and developing treatment system 1 has, as shown in FIG. 1, aconfiguration in which, for example, a cassette station 2 fortransferring 25 wafers W per cassette as a unit from/to the outsideinto/from the coating and developing treatment system 1 and transferringthe wafers W into/out of a cassette C; a processing station 3 includinga plurality of various kinds of processing and treatment units, whichare multi-tiered, for performing predetermined processing or treatmentin a manner of single wafer processing in the photolithography process;and an interface section 4 for delivering the wafers W to/from anexposure processing apparatus 8 provided adjacent to the processingstation 3, are integrally connected.

In the cassette station 2, a cassette mounting table 5 is provided andconfigured such that a plurality of cassettes C can be mounted thereonin a line in an X-direction (a top-to-bottom direction in FIG. 1). Inthe cassette station 2, a wafer transfer body 7 is provided which ismovable in the X-direction on a transfer path 6. The wafer transfer body7 is also movable in a wafer-arrangement direction of the wafers Whoused in the cassette C (a Z-direction; the vertical direction), andthus can selectively access the wafer W in each of the cassettes Carranged in the X-direction.

The wafer transfer body 7 is rotatable in a θ-direction around a Z-axis,and can access a temperature regulating unit 60 for regulating thetemperature of the wafer W and a transition unit 61 for passing thewafer W included in a later-described third processing unit group G3 onthe processing station 3 side.

The processing station 3 adjacent to the cassette station 2 includes,for example, five processing unit groups G1 to G5 in each of which aplurality of processing and treatment units are multi-tiered. On theside of the negative direction in the X-direction (the downwarddirection in FIG. 1) in the processing station 3, the first processingunit group G1 and the second processing unit group G2 are placed inorder from the cassette station 2 side. On the side of the positivedirection in the X-direction (the upward direction in FIG. 1) in theprocessing station 3, the third processing unit group G3, the fourthprocessing unit group G4, and the fifth processing unit group G5 areplaced in order from the cassette station 2 side. Between the thirdprocessing unit group G3 and the fourth processing unit group G4, afirst transfer unit A1 is provided, and a first transfer arm 10 thatsupports and transfers the wafer W is provided inside the first transferunit A1. The first transfer arm 10 can selectively access the processingand treatment units in the first processing unit group G1, the thirdprocessing unit group G3, and the fourth processing unit group G4 andtransfer the wafer W to them. Between the fourth processing unit groupG4 and the fifth processing unit group G5, a second transfer unit A2 isprovided, and a second transfer arm 11 that supports and transfers thewafer W is provided inside the second transfer unit A2. The secondtransfer arm 11 can selectively access the processing and treatmentunits in the second processing unit group G2, the fourth processing unitgroup G4, and the fifth processing unit group G5 and transfer the waferW to them.

In the first processing unit group G1, as shown in FIG. 2, solutiontreatment units each for supplying a predetermined liquid to the wafer Wto perform treatment, for example, resist coating units 20, 21, and 22each for applying a resist solution to the wafer W, and bottom coatingunit 23 and 24 each for forming an anti-reflection film that preventsreflection of light at the time of exposure processing, are five-tieredin order from the bottom. In the second processing unit group G2,solution treatment units, for example, developing treatment units 30 to34 each for supplying a developing solution to the wafer W to develop itare five-tiered in order from the bottom. Further, chemical chambers 40and 41 for supplying various kinds of treatment solutions to thesolution treatment units in the processing unit groups G1 and G2 areprovided at the lowermost tiers of the first processing unit group GIand the second processing unit group G2, respectively.

As shown in FIG. 3, in the third processing unit group G3, for example,the temperature regulating unit 60, the transition unit 61,high-precision temperature regulating units 62 to 64 each for regulatingthe temperature of the wafer W under a high precision temperaturecontrol, and high-temperature thermal processing units 65 to 68 each forheat-processing the wafer W at a high temperature, are nine-tiered inorder from the bottom.

In the fourth processing unit group G4, for example, a high-precisiontemperature regulating unit 70, pre-baking units 71 to 74 each forheat-processing the wafer W after resist coating treatment, andpost-baking units 75 to 79 each for heat-processing the wafer W afterdeveloping treatment, are ten-tiered in order from the bottom.

In the fifth processing unit group G5, a plurality of thermal processingunits each for thermally processing the wafer W, for example,high-precision temperature regulating units 80 to 83, and post-exposurebaking units 84 to 89, are ten-tiered in order from the bottom.

As shown in FIG. 1, on the positive direction side in the X-direction tothe first transfer unit A1, a plurality of processing and treatmentunits are arranged, for example, adhesion units 90 and 91 each forperforming hydrophobic treatment on the wafer W and heating units 92 and93 each for heating the wafer W being four-tiered in order from thebottom as shown in FIG. 3. As shown in FIG. 1, on the positive directionside in the X-direction to the second transfer unit A2, for example, anedge exposure unit 94 is disposed which selectively exposes only theedge portion of the wafer W to light.

In the interface section 4, for example, a wafer transfer body 101moving on a transfer path 100 extending in the X-direction, a buffercassette 102, and a coating film processing unit group G6 are providedas shown in FIG. 1. The buffer cassette 102 is disposed on the positivedirection side in the X-direction (the upward direction in FIG. 1) inthe interface section 4, and the coating film processing unit group G6is disposed on the negative direction side in the X-direction (thedownward direction in FIG. 1). The wafer transfer body 101 is movable inthe Z-direction and also rotatable in the θ-direction, and thus canaccess the exposure processing apparatus 8 adjacent to the interfacesection 4, the buffer cassette 102, the coating film processing unitgroup G6, and the fifth processing unit group G5 and transfer the waferW to them.

As shown in FIG. 2, for example, coating film forming apparatuses 300 attwo tiers each for forming a coating film on the rear surface of thewafer W and coating film removing apparatuses 200 at two tiers each forremoving the coating film on the rear surface of the wafer W accordingto the embodiment are stacked in order from the bottom in the coatingfilm processing unit group G6.

Next, the configuration of the above-described coating film removingapparatus 200 will be described based on FIG. 4. The coating filmremoving apparatus 200 has a treatment container 250 whose inside can beclosed. On one side surface of the treatment container 250, atransfer-in/out port 251 for the wafer W is provided in a surface facinga transfer-in region for the wafer transfer body 101 being a transfermeans for the wafer W, and an opening/closing shutter 252 is provided atthe transfer-in/out port 251.

Inside the treatment container 250, as shown in FIG. 5, a wafer deliverytable 240 for mounting the wafer W transferred thereinto through thetransfer-in/out port 251. On the wafer delivery table 240, for example,three support pints 240 a for supporting the wafer W are provided.

Inside the treatment container 250, a transfer arm 260 is provided whichtransfers the wafer W between the wafer delivery table 240 and alater-described spin chuck 220. The transfer 260 has a pair of chuckportions 261 capable of approaching to and separating from each other asshown in FIG. 6. The chuck portion 261 has a flame portion 261 a formedin a quarter ring, and an arm portion 261 b integrally formed with theflame portion 261 a for supporting the flame portion 261 a. The flameportions 261 a are provided with respective wafer clamp portions 262,and tapered grooves 262 a are formed in the side surfaces of the waferclamp portions 262 as shown in FIG. 7. The pair of separated chuckportions 261 approach to each other, whereby peripheral portions of thewafer W are inserted into the tapered grooves 262 a so that the wafer Wis supported.

The transfer arm 260 is supported by a turning mechanism 263 as shown inFIG. 6. The turning mechanism 263 has a drive unit (not shown) such as amotor or the like therein, and allows the transfer arm 260 to turnaround the horizontal axis (around the X-axis) and expand and contractin the horizontal direction (the X-direction). In other words, the frontand rear surfaces of the wafer W held by the transfer arm 260 can beinverted, and the wafer W can be moved in the horizontal direction (theX-direction). A shaft 264 is provided on the lower surface of theturning mechanism 263, and the lower end of the shaft 264 is connectedto a raising and lowering mechanism 265. The raising and loweringmechanism 265 has a drive unit (not shown) such as a motor or the liketherein, and can raise and lower the turning mechanism 263 and thetransfer arm 260. The raising and lowering mechanism 265 is supported bya transfer mechanism 266, and the transfer mechanism 266 allows theraising and lowering mechanism 265, the turning mechanism 263, and thetransfer arm 260 to move along a guide rail 267 provided along thelongitudinal direction (the Y-direction) of the treatment container 250as shown in FIG. 5. In other words, the wafer W supported by thetransfer arm 260 can be transferred in the treatment container 250.

Inside the treatment container 250, a spin chuck 220 as a substrateholding unit is provided which horizontally holds the wafer W with therear surface of the wafer W directed upward as shown in FIG. 4. The spinchuck 220 can rotate around the vertical axis and raise and lower bymeans of a rotating mechanism 221 including a motor and the like. On theupper surface of the spin chuck 220, for example, eight holding pins 222for holding the peripheral portion of the wafer W are provided along theperipheral portion of the wafer W as shown in FIG. 8. The holding pin222 has a horizontal holding surface 222 a for directly holding thewafer W and a vertical wall 222 b parallel to the peripheral side edgeof the wafer W as shown in FIG. 9, and the top portion of the verticalwall 222 b has a height to protrude from the upper surface of the waferW when the wafer W is held on the holding surface 222 a. At the centralportion of the upper surface of the spin chuck 220, a recessed portion224 is formed downward as shown in FIG. 8, so that a space 223 is formedbetween the recessed portion 224 and the wafer W.

At the central portion of the upper surface of the spin chuck 220, a gassupply port 224 a is formed which jets an inert gas, for example,nitrogen gas toward the space 223, and a gas supply pipe 225 penetratingthrough the spin chuck 220 is connected to the gas supply port 224 a.The inert gas jetted from the gas supply port 224 a toward the space 223flows from the side of the lower surface of the wafer W, then around theperipheral side edge, to the upper surface. Then, the pressure of theinert gas flowing around to the side of the upper surface of the wafer Wpresses and fixes the wafer W onto the holding pins 222. For thistechnique, the publicly known technique described in JP H3-52226 can beemployed.

Around the spin chuck 220, a cup body 226 is provided as shown in FIG.4. The cup body 226 has an opening portion formed in its upper facewhich is larger than the wafer W and the spin chuck 220 to allow thespin chuck 220 holding the wafer W thereon to rise and lowertherethrough. The bottom portion of the cup body 226 is formed withdrain ports 227 for draining a coating solution or a rinse solutiondropping out of the top of the wafer W, and drain pipes 228 areconnected to the drain ports 227.

Above the spin chuck 220, a removing solution supply nozzle 230 islocated for supplying the removing solution for removing the coatingfilm onto the central portion of the rear surface of the wafer W asshown in FIG. 4. The removing solution supply nozzle 230 is connected toa removing solution supply source 232 via a removing solution supplypipe 231. The removing solution supply pipe 231 is provided with asupply controller 233 including a valve, a flow control unit, and so on.The removing solution supplied from the removing solution supply source232 is selectively used depending on the kind of the coating film formedon the rear surface of the wafer W, so that, for example, when thecoating film is an SOG (Spin On Glass) film, a treatment solution suchas hydrofluoric acid is used as the removing solution. Besides, when thecoating film is, for example, a resist film of an organic material,PGMEA or the like, or acetone-based or ketone-based solvent is used asthe removing solution.

The removing solution supply nozzle 230 is connected to a movingmechanism 235 via an arm 234 as shown in FIG. 5. The arm 234 isconfigured such that it can be moved by the moving mechanism 235 along aguide rail 236 provided along the longitudinal direction (theY-direction) of the treatment container 250, from a waiting region 237provided outside on the side of one end of the cup body 226 (the rightside in FIG. 5) toward the other end side and vertically moved. Thewaiting region 237 is configured to be able to accommodate the removingsolution supply nozzle 230 and includes a cleaning portion 237 a whichcan clean the tip end portion of the removing solution supply nozzle230.

Above the spin chuck 220, a rinse nozzle 270 is located for cleaning therear surface of the wafer W after the coating film is removed as shownin FIG. 4. The rinse nozzle 270 is connected to a rinse solution supplysource 272 via a rinse solution supply pipe 271. The rinse solutionsupply pipe 271 is provided with a supply controller 273 including avalve, a flow control unit, and so on. As the rinse solution suppliedfrom the rinse solution supply source 272, for example, pure water isused.

An arm 274 and a moving mechanism 275 connected to the rinse nozzle 270have the same configuration as those of the arm 234 and the movingmechanism 235 as shown in FIG. 5. The moving mechanism 275 of the rinsenozzle 270 and the moving mechanism 235 of the removing solution supplynozzle 230 share the guide rail 236. The arm 274 of the rinse nozzle 270is configured such that it can be moved by the moving mechanism 275along the guide rail 236, from a waiting region 276 provided outside onthe side of one end of the cup body 226 (the left side in FIG. 5) towardthe other end side and vertically moved. The waiting region 276 isconfigured to be able to accommodate the rinse nozzle 270 and includes acleaning portion 276a which can clean the tip end portion of the rinsenozzle 270.

Next, the configuration of the above-described coating film formingapparatus 300 will be described based on FIG. 10. The coating filmforming apparatus 300 has a treatment container 350 whose inside can beclosed. On one side surface of the treatment container 350, atransfer-in/out port 351 for the wafer W is provided in a surface facinga transfer-in region for the wafer transfer body 101 being a transfermeans for the wafer W, and an opening/closing shutter 352 is provided atthe transfer-in/out port 351. Inside the treatment container 350, apartition member 353 is provided that partitions the inside of thetreatment container 350 into a first treatment chamber 311 and a secondtreatment chamber 312, and the insides of the first treatment chamber311 and the second treatment chamber 312 are closable, respectively. Thepartition member 353 is formed with a passing port 354 through which alater-described transfer arm 360, turning mechanism 363, raising andlowering mechanism 365, and transfer mechanism 366 can pass, and anopening and closing shutter 355 is provided at the passing port 354.

Inside the first treatment chamber 311, a wafer delivery table 340 isprovided for mounting the wafer W transferred thereinto through atransfer-in/out port 351 as shown in FIG. 11. On the wafer deliverytable 340, for example, three support pints 340 a for supporting thewafer W are provided.

Inside the coating film forming apparatus 300, a transfer arm 360 isprovided which receives the wafer W from the wafer delivery table 340and transfers the wafer W between the first treatment chamber 311 andthe second treatment chamber 312. The transfer arm 360 has the sameconfiguration as that of the transfer arm 260 in the coating filmremoving apparatus 200 and thus can hold the wafer W.

The turning mechanism 363 for supporting the transfer arm 360, a shaft364 connected to the lower surface of the turning mechanism 363, theraising and lowering mechanism 365 connected to the lower end portion ofthe shaft 364, and the transfer mechanism 366 for supporting the raisingand lowering mechanism 365 have the same configurations as those of theturning mechanism 263, the shaft 264, the raising and lowering mechanism265, and the transfer mechanism 266 in the coating film removingapparatus 200, and thus can invert the front and rear surfaces of thewafer W held by the transfer arm 360, and move the wafer W in thehorizontal direction (the X-direction) and raise and lower the wafer W.

A guide rail 367 on which the transfer mechanism 366 moves is providedalong the longitudinal direction (the Y-direction) of the treatmentcontainer 350 as shown in FIG. 11 to allow the wafer W supported by thetransfer arm 360 to be transferred between the first treatment chamber311 and the second treatment chamber 312.

Inside the first treatment chamber 311, a spin chuck 320 is providedwhich horizontally holds the wafer W with the rear surface of the waferW directed upward as shown in FIG. 10. The spin chuck 320 has the sameconfiguration as that of the spin chuck 220 in the coating film removingapparatus 200 and can be rotated around the vertical axis and raised andlowered by a rotating mechanism 321, and the wafer W can be fixed to thespin chuck 320 with the rear surface of the wafer W directed upward.

A cup body 326 provided around the spin chuck 320, drain ports 327provided in the bottom portion of the cup body 326, drain pipes 328connected to the drain ports 327 have the same configurations as thoseof the cup body 226, the drain ports 227, and the drain pipes 228 in thecoating film removing apparatus 200.

Above the spin chuck 320, a coating nozzle 330 is located for supplyinga coating solution onto the central portion of the rear surface of thewafer W. The coating nozzle 330 is connected to a coating solutionsupply source 332 via a coating solution supply pipe 331. The coatingsolution supply pipe 331 is provided with a supply controller 333including a valve, a flow control unit, and so on. As the coatingsolution supplied from the coating solution supply source 332, forexample, SOG material, or a resist of an organic material or the like isused.

The coating nozzle 330 is connected to a moving mechanism 335 via an arm334 as shown in FIG. 11. The arm 334 is configured such that it can bemoved by the moving mechanism 335 along a guide rail 336 provided alongthe Y-direction of the first treatment chamber 311, from a waitingregion 337 provided outside on the side of one end of the cup body 326(the right side in FIG. 11) toward the other end side and verticallymoved. The waiting region 337 is configured to be able to accommodatethe coating nozzle 330 and includes a cleaning portion 337 a which canclean the tip end portion of the coating nozzle 330.

In an upper portion of the second treatment chamber 312, a lamp heatingunit 341 is provided which cures the coating solution applied on thewafer W as shown in FIG. 10. The lamp heating unit 341 can cure thecoating solution on the wafer W by heating the wafer W.

The coating and developing treatment system 1 incorporating the coatingfilm removing apparatus 200 according to this embodiment is configuredas described above, and the photolithography processing and variouskinds of treatments performed on the wafer W after completion of thephotolithography processing which are performed in this coating anddeveloping treatment system 1 will be described next. FIG. 12 is a flowshowing the procedure of the wafer treatment.

First of all, one wafer W is taken out of the cassette C on the cassettemounting table 5 by the wafer transfer body 7 and transferred to thetemperature regulating unit 60 in the third processing unit group G3.The wafer W transferred to the temperature regulating unit 60 istemperature-regulated to a predetermined temperature and is thentransferred by the first transfer arm 10 into bottom coating unit 23,where an anti-reflection film is formed. The wafer W above which theanti-reflection film has been formed is transferred by the firsttransfer arm 10 to the heating unit 92, the high-temperature thermalprocessing unit 65, and the high-precision temperature regulating unit70 in sequence so that predetermined processing is performed in each ofthe units. Thereafter, the wafer W is transferred to the resist coatingunit 20.

After a resist film has been formed over the front surface of the waferW in the resist coating unit 20, the wafer W is transferred by the firsttransfer arm 10 to the pre-baking unit 71 and subjected to heatingprocessing and subsequently transferred by the second transfer arm 11 tothe edge exposure unit 94 and the high-precision temperature regulatingunit 83 in sequence so that the wafer W is subjected to predeterminedprocessing in each of the units. Thereafter, the wafer W is transferredby the wafer transfer body 101 in the interface section 4 to theexposure processing apparatus 8. In the exposure processing apparatus 8,the rear surface of the wafer W is suction-held, and the resist filmabove the wafer W is exposed to light under a predetermined pattern(Step S1 in FIG. 12). The wafer W for which exposure processing has beenfinished is transferred by the wafer transfer body 101 to the coatingfilm forming apparatus 300 (Step S2 in FIG. 12).

The wafer W transferred into the treatment container 350 through itstransfer-in/out port 351 is mounted on the wafer delivery table 340 bythe wafer transfer body 101. Then, the turning mechanism 363 extends thetransfer arm 360 to a position of the wafer delivery table 340 so thatthe transfer arm 360 holds the wafer W.

The turning mechanism 363 then turns and inverts the wafer W held by thetransfer arm 360 to direct the rear surface of the wafer W upward. Inthis state, the transfer mechanism 366 moves the wafer W to above thespin chuck 320. The spin chuck 320 is then raised to pass the wafer Wfrom the transfer arm 360 to the spin chuck 320. The transfer arm 360 isretracted from above the spin chuck 320 and the inert gas is jetted fromthe gas supply port 324 of the spin chuck 320, whereby the wafer W ishorizontally held on the spin chuck 320. The spin chuck 320 is thenlowered to lower the wafer W to a predetermined position.

Subsequently, the rotating mechanism 321 rotates the wafer W, and thecoating nozzle 330 is moved to above the central portion of the wafer W.The coating solution is discharged from the coating nozzle 330 to thecentral portion of the rear surface of the wafer W. The dischargedcoating solution spreads over the rear surface of the wafer W by thecentrifugal force generated by rotation of the wafer W. Thereafter, thecoating nozzle 330 is moved from above the central portion of the waferW to the waiting region 337. Note that the coating solution may beapplied within a range where the rear surface of the wafer W is suckedin the exposure processing apparatus 8, and the coating solution may notbe applied at the peripheral portion of the rear surface of the wafer W.

After spread of the coating solution on the rear surface of the wafer W,the wafer W on the spin chuck 320 is raised to a predetermined position,and the transfer arm 360 is extended to move to above the spin chuck320. The wafer W is passed from the spin chuck 320 to the transfer arm360.

Next, the transfer mechanism 366 moves the wafer W into the secondtreatment chamber 312. The turning mechanism 363, the raising andlowering mechanism 365, and the transfer mechanism 366 adjust theposition of the wafer W so that the wafer W is located directly belowthe lamp heating unit 341 as shown by broken line portions in FIG. 10and FIG. 11. Then, with the wafer W being held by the transfer arm 360,the lamp heating unit 341 heats the wafer W to cure the coating solutionon the rear surface of the wafer W.

After formation of the coating film by curing the coating solution onthe rear surface of the wafer W, the transfer mechanism 366 moves againthe wafer W into the first treatment chamber 311. The turning mechanism363 then turns and inverts the wafer W to direct the front surface ofthe wafer W upward, and the wafer W is passed from the transfer arm 360to the wafer delivery table 340. The wafer W is then transferred by thewafer transfer body 101 to the outside of the coating film formingapparatus 300.

The wafer W having the coating film formed on its rear surface istransferred by the wafer transfer body 101, for example, to thepost-exposure baking unit 84, where the wafer W is subjected topredetermined processing. After completion of the thermal processing inthe post-exposure baking unit 84, the wafer W is transferred by thesecond transfer arm 11 to the high-precision temperature regulating unit81, where the wafer W is temperature-regulated, and then transferred tothe developing treatment unit 30, where developing treatment isperformed on the wafer W so that a pattern is formed in the resist film.The wafer W is then transferred by the second transfer arm 11 to thepost-baking unit 75, where the wafer W is subjected to heatingprocessing, and subsequently transferred to the high-precisiontemperature regulating unit 63, where the wafer W istemperature-regulated. The wafer W is then transferred by the firsttransfer arm 10 to the transition unit 61, and returned by the wafertransfer body 7 to the cassette C, with which a series ofphotolithography process ends.

After the photolithography processing is performed on the wafer W inthis manner (Steps S1 and S2 in FIG. 12), etching treatment is performedto selectively etch the thin film on the wafer W using the patternformed in the resist film above the wafer W as a mask (Step S3 in FIG.12). Then, ashing processing of stripping the resist film remainingabove the wafer W, for example, by generating plasma is performed (StepS4 in FIG. 12), and cleaning treatment of removing contaminants such asmetal and organic substance adhering onto the wafer W is then performed(Step S5 in FIG. 12).

Thereafter, the wafer W is transferred into the coating and developingtreatment system 1 so that the wafer W is subjected to thephotolithography processing for the second time. The wafer W transferredin the interface section 4 after the wafer W is subjected toabove-described predetermined treatment and processing such as theabove-described formation of the resist film and so on in the coatingand developing treatment system 1 is transferred by the wafer transferbody 101 to the coating film removing apparatus 200 in order to removethe coating film on the rear surface of the wafer W before the wafer Wis transferred to the exposure processing apparatus 8 (Step S6 in FIG.12).

The wafer W transferred by the wafer transfer body 101 into thetreatment container 250 is mounted on the wafer delivery table 240. Theturning mechanism 263 then extends the transfer arm 260 to a position ofthe wafer delivery table 240 so that the transfer arm 260 holds thewafer W.

The turning mechanism 263 then turns and inverts the wafer W held by thetransfer arm 260 to direct the rear surface of the wafer W upward. Inthis state, the transfer mechanism 266 moves the wafer W to above thespin chuck 220. The spin chuck 220 is then raised to pass the wafer Wfrom the transfer arm 260 to the spin chuck 220. The transfer arm 260 isretracted from above the spin chuck 260 and the inert gas is jetted fromthe gas supply port 224 a of the spin chuck 220, whereby the wafer W ishorizontally held on the spin chuck 220. The spin chuck 220 is thenlowered to lower the wafer W to a predetermined position.

Subsequently, the rotating mechanism 221 rotates the wafer W, and theremoving solution supply nozzle 230 is moved to above the centralportion of the wafer W. The removing solution is discharged from the 10removing solution supply nozzle 230 to the central portion of the rearsurface of the wafer W. The discharged removing solution spreads overthe rear surface of the wafer W by the centrifugal force generated byrotation of the wafer W to remove the coating film on the rear surfaceof the wafer W. Thereafter, the removing solution supply nozzle 230 ismoved from above the central portion of the wafer W to the waitingregion 237.

After removal of the coating film existing on the rear surface of thewafer W, the rinse nozzle 270 is moved to above the central portion ofthe wafer W so that the rinse solution is discharged from the rinsenozzle 270 to the central portion of the rear surface of the wafer W.The discharged rinse solution spreads on the rear surface of the wafer Wby the centrifugal force to clean the rear surface of the wafer W.

After completion of the cleaning of the rear surface of the wafer W, thewafer W on the spin chuck 220 is raised to a predetermined position, andthe transfer arm 260 is extended to move to above the spin chuck 220.The wafer W is passed from the spin chuck 220 to the transfer arm 260.The turning mechanism 263 then turns and inverts the wafer W to directthe front surface of the wafer W upward, and the wafer W is passed fromthe transfer arm 260 to the wafer delivery table 240. The wafer W isthen transferred by the wafer transfer body 101 to the outside of thecoating film removing apparatus 200.

The wafer W having the coating film on its rear surface removed istransferred by the wafer transfer body 101 to the exposure processingapparatus 8, where the resist film above the wafer W is exposed to lightunder a predetermined pattern (Step S7 in FIG. 12). The wafer W forwhich the exposure processing has been finished is transferred by thewafer transfer body 101 to the coating film forming apparatus 300, wherethe coating film is formed on the rear surface of the wafer W (Step S8in FIG. 12). Thereafter, treatments such as the development of theresist film and so on are performed, with which the photolithographyprocessing ends.

After performance of the photolithography processing for the second timeis performed on the wafer W, etching treatment for the second time (StepS9 in FIG. 12), ashing processing for the second time (Step S10 in FIG.12), and cleaning treatment for the second time (Step S11 in FIG. 12)are performed in sequence. The photolithography processing, etchingtreatment, ashing processing, and cleaning treatment (Steps S6 to S11 inFIG. 12) are performed in this order a predetermined number of times,whereby multilayer patterns are formed above the wafer W, with which aseries of treatment and processing of wafer W ends.

According to the above embodiment, the coating film is formed on therear surface of the wafer W in the coating film forming apparatus 300immediately after the exposure processing for the wafer W is performedin the exposure processing apparatus 8, so that even if the coating filmon the rear surface of the wafer W gets minute scratches during theetching treatment and the transfer of the wafer W before reaching theexposure processing apparatus 8, the rear surface of the wafer W itselfis protected by the coating film and thus never scratched. In thephotolithography processing subsequently performed, the coating film onthe rear surface of the wafer W is removed in the coating film removingapparatus 200 immediately before the exposure processing is performed inthe exposure processing apparatus 8, so that the rear surface of thewafer W can be flat without projections and depressions for the exposureprocessing. Therefore, the wafer W can be horizontally held during theexposure processing to allow the exposure processing to be appropriatelyperformed.

Planarizing the rear surface of the wafer W before the exposure of thepattern is particularly effective in the case of performing doublepatterning processing that is used for forming a fine pattern on thewafer W. In the double patterning processing, the pattern to be formedin a fine layer on the wafer W is subjected to exposure processing intwice in which the etching treatment is performed after the exposureprocessing for the first time and the exposure processing for the secondtime is performed on the same layer. When the coating and developingtreatment system 1 according to this embodiment is used for the doublepatterning processing, the coating film is formed on the rear surface ofthe wafer W immediately after the exposure processing for the first timeand the coating film is removed immediately before the exposureprocessing for the second time, whereby the rear surface of the wafer Wcan be protected by the coating film during the etching treatment andthe transfer of the wafer W, so that the rear surface of the wafer W canbe flat for the exposure processing. Accordingly, the exposureprocessing in the double patterning processing can be appropriatelyperformed.

Since the coating film forming apparatus 300 and the coating filmremoving apparatus 200 are provided in the coating and developingtreatment system 1, the formation of the coating film on the rearsurface of the wafer W and the removal of the coating film can beperformed in line, thus smoothly performing a series of wafer treatment.

In the first treatment chamber 311 of the coating film forming apparatus300 of the above embodiment, a scribing brush 370 for cleaning the rearsurface of the wafer W may further be provided as shown in FIG. 13. Thescribing brush 370 is located above the spin chuck 320. A cleaningsolution supply port (not shown) is formed in the lower surface of thescribing brush 370, and is connected to a cleaning solution supplysource 372 via a cleaning solution supply pipe 371. The cleaningsolution supply pipe 371 is also provided with a supply controller 373including a valve, a flow control unit, and so on.

The scribing brush 370 is connected to a moving mechanism 375 via an arm374 as shown in FIG. 14. The moving mechanism 375 of the scribing brush370 and the moving mechanism 335 of the coating nozzle 330 share theguide rail 336. The arm 374 of the scribing brush 370 is configured suchthat it can be moved by the moving mechanism 375 along the guide rail336, from a waiting region 376 provided outside on the side of one endof the cup body 326 (the left side in FIG. 14) toward the other end sideand vertically moved. The waiting region 376 is configured to be able toaccommodate the scribing brush 370 and includes a cleaning portion 376 awhich can clean the tip end portion of the scribing brush 370.

In this case, after the wafer W is passed from the transfer arm 360 tothe spin chuck 320, the wafer W is rotated by the rotating mechanism 321and the scribing brush 370 is brought into contact with the rear surfaceof the wafer W. Thereafter, the rear surface of the wafer W is cleanedwhile the cleaning solution is being supplied from the cleaning solutionsupply port of the scribing brush 370. After the contaminants adheringto the rear surface of the wafer W are removed in the above manner, thescribing brush 370 is moved from above the wafer W to the waiting region376. The coating nozzle 330 is moved to above the wafer W and appliesthe coating solution to the rear surface of the wafer W. Thecontaminants adhering to the rear surface of the wafer W are removed bythe scribing brush 370 immediately before the coating solution isapplied from the coating nozzle 330 to the rear surface of the wafer W,thereby ensuring that a coating film to be formed on the rear surface ofthe wafer W thereafter is planarized more reliably.

In place of the removing solution supply nozzle 230 of the coating filmremoving apparatus 200 used in the above embodiment, a removing solutionsupply nozzle 280 may be used which has a discharge port 280 a in a slitform extending in the X-direction as shown in FIG. 15. To the upperportion of the removing solution supply nozzle 280, a removing solutionsupply pipe 281 is connected which leads to a removing solution supplysource 282. The removing solution supply pipe 281 is also provided witha supply controller 283 including a valve, a flow control unit, and soon. As shown in FIG. 16 and FIG. 17, the removing solution supply nozzle280 is formed, for example, longer than the width in the X-direction ofthe wafer W, and is connected to a moving mechanism 285 via an arm 284.The arm 284 can be moved by the moving mechanism 285 along the guiderail 236, from a waiting region 287 provided outside on the side of oneend of the cup body 226 (the right side in FIG. 17) toward the other endside and vertically moved. The waiting region 287 can accommodate theremoving solution supply nozzle 280.

In the case where the removing solution supply nozzle 280 is used asdescribed above, movement of the moving mechanism 285 allows theremoving solution to be discharged from the removing solution supplynozzle 280 to the rear surface of the wafer W. Accordingly, in place ofthe rotating mechanism 221 which rotates and raises and lowers the spinchuck 220, a raising and lowering mechanism 229 may be used which canonly raise and lower the spin chuck 220 as shown in FIG. 16.

For the coating nozzle 330 of the coating film forming apparatus 300used in the above embodiment, a coating nozzle may be used which has theabove-described discharge port in a slit form.

In place of the spin chuck 220 of the coating film removing apparatus200 used in the above embodiment, a spin chuck 400 may be used which hasa removing solution supply nozzle 410 and a rinse nozzle 420 therein asshown in FIG. 18 and FIG. 19. The removing solution supply nozzle 410and the rinse nozzle 420 provided inside the spin chuck 400 areinstalled at a slant each inclining from the vertical direction towardthe center. The removing solution supply nozzle 410 and the rinse nozzle420 can discharge the removing solution and the rinse solution from theupper surface of the spin chuck 400 toward the lower surface of thewafer W, respectively.

The removing solution supply nozzle 410 is connected to a removingsolution supply source 412 via a removing solution supply pipe 411passing through the spin chuck 400. The rinse nozzle 420 is similarlyconnected to a rinse solution supply source 422 via a rinse solutionsupply pipe 421 passing through the spin chuck 400. At the centralportion of the upper surface of the spin chuck 400, a recessed portion402 is formed downward, so that a space 401 is formed between therecessed portion 402 and the wafer W. At the central portion of theupper surface of the spin chuck 400, a gas supply port 402 a is formedwhich jets an inert gas, for example, nitrogen gas toward the space 401,and a gas supply pipe 403 penetrating through the spin chuck 400 isconnected to the gas supply port 402 a. On the upper surface of the spinchuck 400, for example, eight holding pins 404 for holding theperipheral portion of the wafer W are provided along the peripheralportion of the wafer W. The holding pin 404 has the same shape as thatof the holding pin 222.

In this case, the wafer W transferred by the transfer body 101 to thecoating film removing apparatus 200 is passed from the wafer transferbody 101 to the spin chuck 400 by raising the spin chuck 400. The inertgas is then jetted from the gas supply port 402 a toward the space 401to fix the wafer W to the spin chuck 400, and then the wafer W islowered to a predetermined position. The rotating mechanism 221 rotatesthe wafer W, and the removing solution is discharged from the removingsolution supply nozzle 400 to the rear surface of the wafer W to removethe coating film on the rear surface of the wafer W. Thereafter, therinse solution is discharged from the rinse nozzle 410 to the rearsurface of the wafer W to clean the rear surface of the wafer W. Usingthe coating film removing apparatus 200 as described above allows thecoating film on the rear surface of the wafer W to be removed with therear surface of the wafer W directed downward.

Note that in the case where such a spin chuck 400 is used, the removingsolution can be discharged to the rear surface of the wafer W with thefront surface of the wafer W directed upward, so that the wafer deliverytable 140 and the transfer arm 260 which are provided for inverting thewafer W and members and mechanisms associated with them becomeunnecessary and thus may be omitted from the coating film removingapparatus 200.

In place of the spin chuck 220 of the coating film removing apparatus200 used in the above embodiment, three spin chucks 430, 431, and 431may be used which vacuum-sucks the rear surface of the wafer W as shownin FIG. 20. The first spin chuck 430 is located to suction-hold thecentral portion of the wafer W. The second spin chucks 431 and 431 arelocated to suck the position other than the portion which is sucked bythe first spin chuck 430 so that the two spin chucks 431 and 431 holdthe wafer W. Below the spin chucks 430, 431 and 431, a rotatingmechanism 440 is provided which can rotate and raise and lower the firstspin chuck 430 and the second spin chucks 431 and 431 independently.Obliquely below the wafer W held by the spin chucks 430, 431 and 431, aremoving solution supply nozzle 450 and a rinse nozzle 460 areseparately provided in the cup body 226. The removing solution supplynozzle 450 is connected to a removing solution supply source 452 via aremoving solution supply pipe 451. The rinse nozzle 460 is connected toa rinse solution supply nozzle 462 via a rinse solution supply pipe 461.

In this case, the wafer W transferred by the wafer transfer body 101 tothe coating film removing apparatus 200 is passed from the wafertransfer body 101 to the first spin chuck 430 by raising the first spinchuck 430. The wafer W suction-held by the first spin chuck 430 is thenlowered to a predetermined position. The wafer W is then rotated by therotating mechanism 440, and the removing solution is discharged from theremoving solution supply nozzle 450 to the rear surface of the wafer Wto remove the coating film on the rear surface at a portion other thanthe portion which is sucked by the first spin chuck 430.

Subsequently, the rotation of the wafer W is stopped, the second spinchucks 431 and 431 are raised to suction-hold the rear surface of thewafer W, and the first spin chuck 430 is lowered. The wafer W is thenrotated again, and the removing solution is discharged from the removingsolution supply nozzle 450 to the rear surface of the wafer W to removethe coating film at the central portion which has been sucked by thefirst spin chuck 430. As a result, the coating solution on the entirerear surface of the wafer W can be removed.

Thereafter, the rinse solution is discharged from the rinse nozzle 460to the rear surface of the wafer W to clean the rear surface of thewafer W. For this cleaning, the rear surface of the wafer W is cleanedin twice in which cleaning is performed with the wafer W being sucked bythe first spin chuck 430 and cleaning is performed with the wafer Wbeing sucked by the second spin chucks 431 and 431 whereby the entirerear surface of the wafer W can be cleaned. Using the coating filmremoving apparatus 200 as described above allows the coating film on therear surface of the wafer W to be removed with the rear surface of thewafer W directed downward.

In the case where such spin chucks 430 and 431 are used, the removingsolution can be discharged to the rear surface of the wafer W with thefront surface of the wafer W directed upward, so that the wafer deliverytable 140 and the transfer arm 260 which are provided for inverting thewafer W and members and mechanisms associated with them becomeunnecessary and thus may be omitted from the coating film removingapparatus 200.

In place of the lamp heating unit 341 in the coating film formingapparatus 300 in the above embodiment, any conventional ultravioletirradiation unit (not shown) for applying ultraviolet rays and aconventional electron beam irradiation unit (not shown) for applyingelectron beams to the coating solution applied on the wafer W may beprovided. This allows selective use of the lamp heating unit 341, theultraviolet irradiation unit, or the electron beam irradiation unitdepending on the kind of the coating solution in use.

Although the coating film removing apparatus 200 is provided in thecoating and developing treatment system 1 in the above embodiment, thecoating film removing apparatus 200 may be provided outside the coatingand developing treatment system 1. As such an example, a coating filmremoving system 500 has, as shown in FIG. 21 and FIG. 22, aconfiguration in which, for example, a cassette station 501 fortransferring 25 wafers W per cassette as a unit from/to the outsideinto/from the coating film removing system 500 and transferring thewafers W into/out of a cassette C; and a treatment station 502 forperforming treatment of removing the coating film on the rear surface ofthe wafer W, are integrally connected.

In the cassette station 501, a cassette mounting table 503 is providedand configured such that a plurality of cassettes C can be mountedthereon in a line in an X-direction (a top-to-bottom direction in FIG.21). In the cassette station 501, a wafer transfer body 505 is providedwhich is movable in the X-direction on a transfer path 504. The wafertransfer body 505 is also movable in a wafer-arrangement direction ofthe wafers W housed in the cassette C (a Z-direction; the verticaldirection), and thus can selectively access the wafer W in each of thecassettes C arranged in the X-direction. The wafer transfer body 505 isrotatable in a θ-direction around a Z-axis, and can access alater-described coating film removing apparatus 200 on the treatmentstation 502 side.

On the side of the positive direction in the X-direction (the upwarddirection in FIG. 21) in the treatment station 502, treatment unitgroups G10 and G20 are placed in order from the cassette station 501side, and on the side of the negative direction in the X-direction (thedownward direction in FIG. 21), treatment unit groups G30 and G40 areplaced in order from the cassette station 501 side. Between thetreatment unit groups G10 and G20, and the treatment unit groups G30 andG40, a wafer transfer body 507 which is movable in the Y-direction on atransfer path 506 is provided. The wafer transfer body 507 is alsomovable in the X-direction and the vertical direction (the Z-direction)and rotatable in the θ-direction around the Z-axis to selectively accessthe treatment units in the treatment unit groups G10, G20, G30, and G40and transfer the wafer W to them.

In each of the treatment unit groups G30 and G40, as shown in FIG. 22,the coating film removing apparatuses 200 are four-tiered. Also in eachof the treatment unit groups G10 and G20, the coating film removingapparatuses 200 are four-tiered. More specifically, a total of 16coating film removing apparatuses 200 are provided in the treatmentstation 502. Since the plurality of coating film removing apparatuses200 are provided in the coating film removing system 500, the coatingfilms on the rear surfaces of a plurality of wafers W can be removed atthe same time.

The removal of the coating film on the rear surface of the wafer W bythe coating film removing system 500 is performed, for example, afterthe etching treatment of the wafer W and before the ashing processing(an arrow a in FIG. 23). Thereby, even if the coating film on the rearsurface of the wafer W gets minute scratches during performance of theetching treatment, the rear surface of the wafer W itself is protectedby the coating film and thus never scratched, so that the rear surfaceof the wafer W can be flat for the exposure processing to be performedsubsequent thereto. Note that the removal of the coating film by thecoating film removing system 500 may be performed after the ashingprocessing and before the cleaning treatment (an arrow b in FIG. 23), orafter the cleaning treatment and before the photolithography processing(an arrow c in FIG. 23).

Although the coating film forming apparatus 300 is provided in thecoating and developing treatment system 1 in the above embodiment, thecoating film forming apparatus 300 may be provided outside the coatingand developing treatment system 1. As such an example, a coating filmforming system 600 has a configuration in which treatment unit groupsG50 to G80 as shown in FIG. 24, in place of the treatment unit groupsG10 to G40 of the coating film removing system 500. In each of thetreatment unit groups G50 to G80, the coating film forming apparatuses300 are four-tiered.

The formation of the coating film on the rear surface of the wafer W bythe coating film forming system 600 is performed, for example, after thephotolithography processing for the wafer W and before the etchingtreatment (an arrow d in FIG. 23). Thereby, even if the coating film onthe rear surface of the wafer W gets minute scratches during the etchingtreatment, the rear surface of the wafer W itself is protected by thecoating film and thus never scratched, so that the rear surface of thewafer W can be flat for the exposure processing subsequent thereto. Notethat the formation of the coating film on the rear surface of the waferW by the coating film forming system 600 may be performed before thephotolithography processing performed for the first time (an arrow e inFIG. 23).

Although the inside of the coating film forming apparatus 300 is dividedinto the first treatment chamber 311 and the second treatment chamber312 in the above embodiment, the first treatment chamber 311 and thesecond treatment chamber 312 may be divided into separate units. Morespecifically, the coating film forming apparatus 300 may be divided intoa unit for applying the coating solution from the coating nozzle 330 tothe rear surface of the wafer W and a unit for heating the wafer W usingthe lamp heating unit 341 to cure the coating solution on the rearsurface of the wafer W.

Although the coating film is formed on the rear surface of the wafer Wby applying the coating solution in the above embodiment, a thin filmmay be formed on the rear surface of the wafer W, for example, by theCVD (Chemical Vapor Deposition) method. In other words, a material gasmay be supplied to the rear surface of the wafer W to deposit into athin film on the rear surface of the wafer W by chemical catalyticreaction so as to protect the rear surface of the wafer W.

Preferred embodiments of the present invention have been described abovewith reference to the accompanying drawings, but the present inventionis not limited to the embodiments. It should be understood that variouschanges and modifications within the scope of the spirit as set forth inclaims are readily apparent to those skilled in the art, and thoseshould also be covered by the technical scope of the present invention.The present invention is also applicable, for example, to the case wherethe substrate is a substrate other than the wafer, such as an FPD (FlatPanel Display), a mask reticle for a photomask, or the like.

The present invention is useful to a method of treating a substrate, forexample, a semiconductor wafer or the like, a coating film removingapparatus, and a substrate treatment system.

1. A substrate treatment method of performing at least photolithographyprocessing and etching treatment for a substrate in this order aplurality of times, comprising the steps of: forming a coating film on arear surface of the substrate after exposure processing in thephotolithography processing is performed; and removing the coating filmbetween the formation of the coating film and performance of nextexposure processing.
 2. The substrate treatment method as set forth inclaim 1, wherein said step of forming a coating film comprises the stepsof: inverting the substrate to direct the rear surface of the substrateupward; applying a coating solution to the rear surface of thesubstrate; and curing the coating solution applied on the rear surfaceof the substrate.
 3. The substrate treatment method as set forth inclaim 1, wherein said step of removing the coating film comprises thestep of supplying a removing solution to the coating film.
 4. Thesubstrate treatment method as set forth in claim 3, wherein said step ofremoving the coating film comprises the step of, before supplying theremoving solution to the coating film, inverting the substrate to directthe rear surface of the substrate upward.
 5. The substrate treatmentmethod as set forth in claim 1, further comprising the step of:immediately before said step of forming a coating film, cleaning therear surface of the substrate.
 6. The substrate treatment method as setforth in claim 2, wherein the coating solution applied on the rearsurface of the substrate is cured by being heated.
 7. The substratetreatment method as set forth in claim 2, wherein the coating solutionapplied on the rear surface of the substrate is cured by beingirradiated with ultraviolet rays or electron beams.
 8. A coating filmremoving apparatus for removing a coating film formed on a rear surfaceof a substrate, comprising: a transfer arm transferring the substrate; aturning mechanism supporting said transfer arm and turning said transferarm around a horizontal axis; a raising and lowering mechanismsupporting said turning mechanism and raising and lowering said turningmechanism; a transfer mechanism supporting said raising and loweringmechanism and transferring said raising and lowering mechanism in thehorizontal direction; a substrate holding unit horizontally holding thesubstrate with the rear surface of the substrate directed upward; and aremoving solution supply nozzle supplying a removing solution for thecoating film to the rear surface of the substrate held by said substrateholding unit.
 9. The coating film removing apparatus as set forth inclaim 8, wherein a rotating mechanism rotating said substrate holdingunit around a vertical axis is provided below said substrate holdingunit.
 10. The coating film removing apparatus as set forth in claim 8,wherein said removing solution supply nozzle is a nozzle having adischarge port in a slit form extending in a direction of a width of thesubstrate.
 11. A substrate treatment system including a coating filmremoving apparatus for removing a coating film formed on a rear surfaceof a substrate and an exposure processing apparatus for performingexposure processing on the substrate, said coating film removingapparatus comprising: a transfer arm transferring the substrate; aturning mechanism supporting said transfer arm and turning said transferarm around a horizontal axis; a raising and lowering mechanismsupporting said turning mechanism and raising and lowering said turningmechanism; a transfer mechanism supporting said raising and loweringmechanism and transferring said raising and lowering mechanism in thehorizontal direction; a substrate holding unit horizontally holding thesubstrate with the rear surface of the substrate directed upward; and aremoving solution supply nozzle supplying a removing solution for thecoating film to the rear surface of the substrate held by said substrateholding unit.
 12. The substrate treatment system as set forth in claim11, further comprising: a coating film forming apparatus for forming thecoating film on the rear surface of the substrate.